This invention relates to a new photographic element containing a novel blocked photographically useful compound that is capable of more rapidly releasing the photographically useful group of the compound upon photographic processing.
Various compounds, such as couplers and dyes, are known in the photographic art that contain a blocking group and that are capable of being released or unblocked upon processing of the photographic material containing the compound. Such compounds and various blocking groups have been described in, for example, U.S. Pat. Nos. 4,690,885; 4,358,525 and 4,554,243 and U.S Pat. No. 5,019,492. While these compounds have enabled increased storage stability compared to compounds that are not blocked and have provided release of the photographically useful group from the compound upon processing, often the stability of the compounds during storage prior to exposure and processing of the photographic materials containing the compounds has not been entirely satisfactory and the rate of release or unblocking of the compound has been less than desired.
A continuing need has existed for a blocked photographically useful compound containing a blocking group that enables a means of tailoring the ballasting of such compounds without adverse effects upon a photographic material.